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In this paper, a study was carried out to investigate the surface roughness and material removal rate of low carbon NiTi shape memory alloy (SMA) machined by Wire Electro Spark Erosion (WESE) technique. Experiments are designed considering three parameters viz, spark ON time (SON), spark OFF time (SOFF), and voltage (V) at three levels each. The surface roughness increased from 2.1686 μm to 2.6869 μm with an increase in both SON time, SOFF time and a decrease in voltage. The material removal rate increased from 1.272 mm3/min to 1.616 mm3/min with an increase in SON time but a varying effect was observed the SOFF time and voltage were varied. The analysis revealed that the intensity and duration of the spark had an unswerving relation with the concentration of the microcracks and micropores. More microcracks and micropores were seen in the combination of SON = 120 µs, voltage = 30 V. The concentration of the microcracks and micropores could be minimised by using an appropriate parameter setting. Therefore, considering the surface analysis and material removal, the low carbon NiTi alloy is recommended to machine with 110 μs – 55 μs – 30 v (SON – SOFF – V respectively), to achieve better surface roughness with minimal surface damage.

This study explores the mechanical, water absorption, and erosive wear properties of hybrid polymer composites reinforced with treated hemp, carbon, and basalt fibers. The composites were fabricated using the hand lay-up method, with epoxy resin as the matrix and fillers (CaCO3 and coconut fiber) incorporated to enhance performance. Treated hemp fibers underwent 5% NaOH treatment to improve fiber-matrix adhesion, and ASTM standards were followed for tensile, flexural, and impact tests. Water absorption was monitored over 10 days, and solid particle erosion was assessed under varying impingement angles. Results showed that Sample B2 (20% treated hemp, 6% basalt) exhibited superior mechanical properties, including flexural strength (15% higher than comparable samples) and impact resistance (10% higher). Treated fibers and fillers minimized water absorption, while erosion resistance was maximized in carbon-basalt composites. SEM analysis confirmed uniform fiber dispersion and strong interfacial bonding in optimal samples, leading to improved load transfer and mechanical stability. This study demonstrates the potential of hybrid composites as high-performance materials for automotive, aerospace, and construction applications, emphasizing the critical role of balanced fiber composition and chemical treatments in optimizing material properties. [ABSTRACT FROM AUTHOR]

The high temperature oxidation and hot corrosion behavior of nickel–iron-based superalloy are studied at 900 ° and 1000 °C. The significant role of alloying elements with respect to the exposed medium is studied in detail. The mass change per unit area was catastrophic for the samples exposed at 1000 °C and gradual increase in mass change was observed at 900 °C for both the environments. The exposed samples were further investigated with SEM, EDS and XRD analysis to study the metallurgical characteristics. The surface morphology has expressed the in situ nature of the alloy and its affinity toward the environment. The EDS and XRD analysis has evidently proved the presence of protective oxides formation on prolonged exposure at elevated temperature. The predominant oxide formed during the exposure at high temperature has a major contribution toward the protection of the samples. The nickel–iron-based superalloy is less prone to oxidation and hot corrosion when compared to the existing alloy in gas turbine engine simulating marine environment.